Less realistic and more artistic post-effects are also possible.
Many of the post-effects supported with YEBIS are designed to create convincing photo-realistic visuals. However, ‘realism’ is not the only field that YEBIS excels in. In fact, some post-effects are extremely well-suited to artistic expression.
Light ray effects such as bloom and glare come under this category. Even better examples are the stunning post-effects such as God Rays, Corona and Heat Shimmer.
God Ray is an effect in which streams of light radiate from a light source. YEBIS, may, in some cases, appear to be performing high-grade volume rendering, however this is actually done via post-effects.
The God Ray effect is effective for showing light filtering through trees or between clouds. The key point is the creation of a mask covering most of the light source, with some of the light being projected out through the openings.
The God Ray effect is achieved by first rendering the scene in HDR, and then introducing a blur from the high luminosity area created with the tone mapping effect in the direction of the light source (or the ray shapes ). Introducing a uniform blur results in thick beams of light and then making the beams thin, produces a glare type beam of lighting. Thus, for the God Ray effect, a mask pattern shielding the light source (the source of the rays) is created based on the depth buffer left after rendering the scene. The high luminosity area blur is created by extracting appropriate pieces of the mask pattern. In YEBIS, a fixed amount of noise is further applied to this mask to create a bundle of countless fine light beams appearing to radiate from the opening in the covered area.
An effect that works very well when combined with God Ray to create impressive visuals is the Corona effect. A Corona is caused by the diffraction of light due to particulate matter in the atmosphere, and appears as a rainbow colored circle. With YEBIS, the Corona can be fully customized by setting the parameters for strength, size, damping ratio, dispersal direction, etc. Depending on the parameter settings, multiple rings or lenticular halos can also be created.
Heat Shimmer effectDOWNLOAD High Resolution Movie
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With the Heat Shimmer effect, the image appears to sway and shimmer. YEBIS allows customizing of the strength of the effect, or restricting them to a certain area. A mirage floating in a desert is the most intuitive use of this effect, and can be shown by positioning the image behind fire or smoke to create a warped effect. This effect is also referred to as Space Warping. It can be used for non-realistic effects such extreme speed by warping the image behind the trajectory of a high-speed punch or kick. It’s also used for optical camouflage effects in military and sci-fi settings, etc.